TV二次回路两点接地故障的排查方法  

Checking Method for TV Secondary Circuit Two-point Grounding Fault

作　　者：黄大玮 李飞[2] 

机构地区：[1]华中电力科学研究院,湖北武汉430077 [2]中国水电顾问集团贵阳勘测设计研究院,贵州贵阳550081

出　　处：《陕西电力》2011年第10期57-59,62,共4页Shanxi Electric Power

摘　　要：变电站TV二次中性线(N600)如有两点或多点接地时,将会造成保护装置的不正确动作行为。文中首先介绍了TV二次回路一点接地的必要性,然后,从理论上分析了两点接地故障情况下保护装置测量到的电压与正常接线下电压的差异及对保护动作行为的影响。结合实际工作中检查接地情况的一些经验,总结出通过故障后录波图电压的变化情况和检查TV二次公共接地点的接地线电流大小可判断是否有多点接地的方法。最后用一个实例验证了该方法的有效性与可靠性。If there are two or more points grounding existing in TV secondary neutral line, it will result in the protection devices＇ incorrect acting. This paper expounds the necessity of secondary circuit one-point grounding, analyzes theoretically the differences of voltage and influences on protection devices between earth-fauh and normal stage. With practical experiences, it can determine whether there are two or more points grounding or not by checking the voltage＇s variation of wave recording after failure and the current of TV secondary common earth-noint. Finally,a case is used to verify the validity and reliability of this method.

关 键 词：电压互感器 二次回路 两点接地 故障录波 

分 类 号：TM451[电气工程—电器] TM772